Re: K3 Notch control

[Dave, G4AON]

While on the subject of the K3 notch, the notch is quite crude compared
to the capabilities of the notch in my SDR receiver. I accept the SDR
has a powerful PC to assist, but the K3 notch is lacking in the
following areas:

On the 80m QRP frequency there is an annoying carrier often present some
70Hz or so above 3560 KHz, my database gives it as Radio Korea. The K3
notch cannot remove the carrier without impacting on any station calling
on 3560. That might seem like a tall order, but the notch in the SDR is
around 70 dB deep and only a few Hz wide at it's narrowest setting. In
addition it is of adjustable width. The SDR removes the carrier
completely without any noticeable impact on a station on 3560.

The K3 notch only sets in 20 Hz steps and is of a fixed width that is
quite wide. Any chance of a review of the K3 notch and it's capabilities?

73 Dave, G4AON
K3/100 #80


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[Ignacy]

I agree that the notch feature in K3 needs serious work.

1. Notch in automatic mode is very slow and incomplete; does not work on slowly drifting carriers
2. In manual mode, the width is way too wide, some 250Hz.
3. It is outside the AGC loop

A standard to follow would be one in IC-7000. Very fast an effective automatic notch. Variable width twin manual notch and; not sure of other Icoms since I do not have any.

I believe that updating the notch should be quite easy compared to other issues.

Ignacy  

[Mike Harris-9]

G'day,

For a bit of balance.  I've got a noise on 20M that has popped up
recently.  Seems to be three tones with 340Hz and 212Hz spacing and about
30dB out of the band noise.  The auto notch takes them all out after a few
seconds thinking.

Not tracked the source yet and there seems to be some activity associated
with the higher tone with the occasional fourth tone showing.  No doubt
some new fangled domestic gadget.

Agree with a narrower manual notch.

Regards,

Mike VP8NO

----- Original Message -----
From: "Ignacy" <[hidden email]>
To: <[hidden email]>
Sent: Thursday, January 08, 2009 11:23 AM
Subject: Re: [Elecraft] K3 Notch control


|
| I agree that the notch feature in K3 needs serious work.
|
| 1. Notch in automatic mode is very slow and incomplete; does not work on
| slowly drifting carriers
| 2. In manual mode, the width is way too wide, some 250Hz.
| 3. It is outside the AGC loop
|
| A standard to follow would be one in IC-7000. Very fast an effective
| automatic notch. Variable width twin manual notch and; not sure of other
| Icoms since I do not have any.
|
| I believe that updating the notch should be quite easy compared to other
| issues.
|
| Ignacy
|

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[Arie Kleingeld PA3A-2]

Well,


Mike wrote: The auto notch takes them all out after a few
seconds thinking.



After a few seconds of thinking.....the K3 notch takes the tones out.
That is also my experience.


Just for comparison: the auto notch of my old 1996 MP (wow DSP!! in
those days) is much faster than the one of the K3. It reacts instantly.

Another point: how about bringing the notch into the AGC loop like a
good notch filter should be.
(Or is that too much to ask. Tell me if it is so. Anyway, that one was
not on Elecrafts short list of DSP impovements when I asked for it two
months ago.)


73,
Arie PA3A


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